graphql: T4753: generalize system_status to composite_{query,mutation}

2 files changed, 130 insertions, 0 deletions

diff --git a/src/services/api/graphql/utils/composite_function.py b/src/services/api/graphql/utils/composite_function.py
new file mode 100644
index 000000000..bc9d80fbb
--- /dev/null
+++ b/src/services/api/graphql/utils/composite_function.py
@@ -0,0 +1,11 @@
+# typing information for composite functions: those that invoke several
+# elementary requests, and return the result as a single dict
+import typing
+
+def system_status():
+    pass
+
+queries = {'system_status': system_status}
+
+mutations = {}
+
diff --git a/src/services/api/graphql/utils/schema_from_composite.py b/src/services/api/graphql/utils/schema_from_composite.py
new file mode 100755
index 000000000..f9983cd98
--- /dev/null
+++ b/src/services/api/graphql/utils/schema_from_composite.py
@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+#
+# A utility to generate GraphQL schema defintions from typing information of
+# composite functions comprising several requests.
+
+import os
+import json
+from inspect import signature, getmembers, isfunction, isclass, getmro
+from jinja2 import Template
+
+if __package__ is None or __package__ == '':
+    from util import snake_to_pascal_case, map_type_name
+else:
+    from . util import snake_to_pascal_case, map_type_name
+
+# this will be run locally before the build
+SCHEMA_PATH = '../graphql/schema'
+
+schema_data: dict = {'schema_name': '',
+                     'schema_fields': []}
+
+query_template  = """
+input {{ schema_name }}Input {
+    key: String!
+    {%- for field_entry in schema_fields %}
+    {{ field_entry }}
+    {%- endfor %}
+}
+
+type {{ schema_name }} {
+    result: Generic
+}
+
+type {{ schema_name }}Result {
+    data: {{ schema_name }}
+    success: Boolean!
+    errors: [String]
+}
+
+extend type Query {
+    {{ schema_name }}(data: {{ schema_name }}Input) : {{ schema_name }}Result @compositequery
+}
+"""
+
+mutation_template  = """
+input {{ schema_name }}Input {
+    key: String!
+    {%- for field_entry in schema_fields %}
+    {{ field_entry }}
+    {%- endfor %}
+}
+
+type {{ schema_name }} {
+    result: Generic
+}
+
+type {{ schema_name }}Result {
+    data: {{ schema_name }}
+    success: Boolean!
+    errors: [String]
+}
+
+extend type Mutation {
+    {{ schema_name }}(data: {{ schema_name }}Input) : {{ schema_name }}Result @compositemutation
+}
+"""
+
+def create_schema(func_name: str, func: callable, template: str) -> str:
+    sig = signature(func)
+
+    field_dict = {}
+    for k in sig.parameters:
+        field_dict[sig.parameters[k].name] = map_type_name(sig.parameters[k].annotation)
+
+    schema_fields = []
+    for k,v in field_dict.items():
+        schema_fields.append(k+': '+v)
+
+    schema_data['schema_name'] = snake_to_pascal_case(func_name)
+    schema_data['schema_fields'] = schema_fields
+
+    j2_template = Template(template)
+    res = j2_template.render(schema_data)
+
+    return res
+
+def generate_composite_definitions():
+    from composite_function import queries, mutations
+
+    results = []
+    for name,func in queries.items():
+        res = create_schema(name, func, query_template)
+        results.append(res)
+
+    for name,func in mutations.items():
+        res = create_schema(name, func, mutation_template)
+        results.append(res)
+
+    out = '\n'.join(results)
+    with open(f'{SCHEMA_PATH}/composite.graphql', 'w') as f:
+        f.write(out)
+
+if __name__ == '__main__':
+    generate_composite_definitions()